Recently, as one form of electric vehicles, a so-called in-wheel motor type vehicle is developed in which a motor is disposed inside a wheel under a spring or in the vicinity of the wheel and the wheel is directly driven by the motor. In the in-wheel motor type vehicle, the motor disposed in each wheel is independently controlled for rotation, that is, the drive (power running) control or regenerative control of each motor is independently performed, and thus the driving force or the braking force provided to each wheel can separately be controlled in response to the travelling state of the vehicle.
With regard to such an in-wheel motor type vehicle, for example, a patent document 1 described below discloses a braking and driving force control apparatus for a vehicle in which the driving force or the braking force to be provided to each wheel is calculated in response to an average sprung displacement and an average sprung speed of the vehicle body, the calculated driving force or braking force is separately applied to the driving force in each wheel during travelling, and thus bouncing of the vehicle body is suppressed.
Additionally, a patent document 2 described below discloses a running system that suppresses behavior change of the vehicle caused by load change above a spring of a suspension device by using an instantaneous rotation angle of a front wheel suspension device and an instantaneous rotation angle of a rear wheel suspension device to calculate front wheel driving force distribution and rear wheel driving force distribution for suppressing the bouncing and calculate the front wheel driving force distribution and the rear wheel driving force distribution for suppressing the pitching.
A patent document 3 described below discloses a vibration suppression device for a vehicle that prevents energy efficiency from decreasing during the suppression of vertical vibrations on the vehicle body by prohibiting at least one of a bouncing suppression control and a pitching suppression control in a case where the braking force is applied to the front wheel or the rear wheel.
Furthermore, a patent document 4 described below discloses a braking and driving force control apparatus for a vehicle that applies different braking and driving forces to each wheel and reduces a pitch moment generated about the center of gravity in order to suppress the vertical vibrations of the vehicle in association with the pitch behavior occurring when the vehicle passes irregularities and the like on a road surface.